Press-to-talk over Cellular (PoC) makes two-way radio service possible over a cellular network and is capable of providing direct one-to-one and one-to-many voice communications service to users of cellular telephones or other mobile communications devices. Calls are started by pressing a button (e.g., a talk button) on the cellular telephone. Press-to-talk over Cellular is based on one-way (half-duplex) communications—while one person speaks, the other(s) listen. When the person who is speaking releases the button, transmission stops and another person can press their talk button to gain the floor. Thus, by pressing the talk button, speakers can take turns responding to each other.
Conventional press-to-talk systems operate on a first-come first-served basis. Since the communications are half-duplex, if person A presses his talk button while person B is speaking, person A's microphone will not be activated, and person B will control the floor as long as his talk button is depressed. Thus, person B cannot be interrupted. Once person B releases his talk button, another speaker (the first speaker to activate his talk switch) can take the floor by pressing his talk button.
In the current usage of a PoC service, participants in a PoC are required to use a tactile scheme to assert floor control to acquire a talking status. The acquisition of the floor or talking status is referred to as talker arbitration. The use of a tactile scheme is not a natural step in the semantics of human conversation, whether in a point-to-point conversation or in a group conversation. A tactile scheme, whether in the form of a dedicated push button on a wireless mobile communication device or in the form of a programmable key on the user interface of a wireless mobile communication device, is not convenient in the context of natural human conversation.
Accordingly, there is a need for a system and method for talker arbitration that is based on a facilitation of the natural dynamics associated with a face-to-face conversation. Further, there is a need for a system and method for talker arbitration that removes the need for a user to push a separate button on the handset before commencement of speech, which is not a natural component of face-to-face conversations.